I really like vultures. Sure, they’re ugly and they eat nasty dead things. But those are not necessarily bad characteristics.

First let’s deal with “ugly.” Vultures’ bald heads are what make them seem ugly to most people. But think about why they’re bald. Imagine thrusting your head inside the carcass of a white-tailed deer to reach the meat. A feathered head might capture bits of flesh, blood and gore and you end up with a face full bacteria and flies. Scientists believe that one reason vultures have evolved featherless heads is to aid in hygiene. A bald head stays clean and any remaining germs or bacteria are baked off by the sun. Vultures have also found that a bald head can help with temperature regulation. When it gets cold they can tuck their heads down to keep their neck covered with feathers. When it’s hot, vultures can extend their neck to expose bare skin. Their bald heads work so well that I wrote a poem about them.

Naked Head

It’s best to have no feathers,

When you stick your head in guts,

That way you don’t go walkin’ round,

Your noggin dripping schmutz.

Moving on to “eating nasty dead things,” the next time you see vultures eating a dead animal on the side of the road, be thankful! That carcass might be dead from rabies or contaminated with other harmful diseases. Vultures have the amazing ability to consume rotting and diseased flesh and stay healthy. It’s all in the stomach. Vultures possess very powerful stomach acids that destroy most bacteria and deadly viruses. In fact, vulture stomach acid is so strong it can dissolve metal! Except if that metal is lead shot -- many turkey vultures are killed every year by consuming shot that they encounter in dead deer. Vultures are the world’s natural “sanitation workers,” helping to stop the spread of disease.

I’m so appreciative of the work they do, I even wrote a poem about eating dead things:

Dead Meat

I like my meat dead,

It’s best if it’s not moving.

Don’t want to see one final twitch,

I prefer it oozing

So, the next time you see a vulture circling in the noonday sky, think about the valuable and important clean up service this bird provides to us and to the environment. Maybe I’ll write a poem about that….

Two magnificent specimens: at right, a turkey vulture showing off his bald head and ,above, an even balder American black vulture. Wikimedia Commons

My friends the black vultures didn't kill this deer. They are just going to be cleaning up the carcass. Wikipedia commons. Photo by Nathaniel Paluga.

Steve Swinburne is a science writer, but as you can see from this Minute, he likes to write poetry too. In his book Ocean Soup, he offers verses in the voices of tide-pool animals, including the barnacle, sea urchin, sculpin, mussel, starfish, hermit crab, anemone, and lobster. For more about Steve's poetry, click here.

Steve Swinburne is a member of iNK's Authors on Call and is available for classroom programs through FieldTripZoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

Daddy longlegs are the spiders we run across the most often, right? Think again.

​ How many body parts does a spider have? Two. A “head” (called a cephalothorax) and an abdomen (where that sticky silk comes from). How many body parts does a daddy longlegs have? One. So, these animals aren’t even spiders. Daddy longlegs are one of many animals called opilionids (oo-pill-ee-OH-nidz). They are in the same animal class as spiders (Arachnida), and they all have long legs so they look like spiders—but they’re a separate order.

Opilionids aren’t dangerous to humans, but their predators had better watch out. Scientist Dr. Thomas Eisner discovered that a daddy longlegs carries toxin in its armpits. His research began one day when travelling through Texas. He picked up a daddy longlegs and smelled it— that’s right, his nose was his scientific instrument. He observed an odd smell so he carted the creature back to his motel room and studied it. The smell was a toxic chemical called benzoquinone (say BEN-zo-qwi-NO-ne). So of course, Dr. Eisner wanted to know more about that!

The chemical is toxic when it is a gas or a liquid, but not when it is a solid. On the side of the animal’s body–basically in its armpit–Dr. Eisner found a sac-like gland. In that gland? Solid benzoquinone.

When a predator such as an ant threatens the daddy longlegs, he spits up a drop of gut juice. That liquid travels down a groove from his mouth to the gland. In less than a second, he dissolves a bit of that benzoquinone into the liquid and creates toxic ammunition. You know those two long legs daddy longlegs use as feelers? He dips the tip of one of them into the toxic drop then slaps it on his predator.

Take that you scary ant! They flee.​ The opilionid can reload his feelers up to thirty times from one toxic drop. When his ammo runs low, all he needs to do is drink water and spit again. Other types of opilionids skip the feelers and just let the liquid ooze out around their body, creating a super toxic safety shield.

​ What other secrets might opilionids be hiding? Not many people study them, so who knows?!? Maybe you will sniff out a discovery!

Some bugs litter. Some pass gas. Some bugs throw their poop! Discover ten of the rudest, crudest bugs around. Full of scientific facts, humor and just the right amount of yuck, Heather L. Montgomery's How Rude! features a countdown of the top 10 bad bugs who just won't mind their manners. One part illustration and one part photography, How Rude! is hilarious, informative, and seriously gross!

Polar bears are built to withstand some of the coldest temperatures on the planet. Their brown and black bear cousins avoid the winter cold by digging dens and sleeping. But, except for pregnant females, polar bears spend the arctic winter outside where temperatures could be -40° F (which equals-40 °C) and windy. That’s too cold for humans. You could go outside, but only for only a few minutes with every part of your body completely covered. And if you didn’t wear goggles, your eyelashes would freeze and break off if you touched them.

Polar bears are warm-blooded like us with a body temperature of about 98°F/37°C. But they are invisible to night-vision goggles that pick up the infrared rays that warm-blooded creatures, including humans, give off. Why? Nature has given polar bears enough insulation to prevent body heat from escaping. They are toasty warm and comfortable in the frigid arctic.

Their heat insulation is in several layers. Under their skin, there is a 4-inch (21.5 cm) layer of fat. Next to the skin is a dense layer of woolly fur that also keeps heat in. The fur you see is a thick layer of long, colorless guard hairs that shed water quickly after a swim. They are stiff and transparent and hollow. In the arctic sunlight, the hairs act like mirrors and reflect white light, which acts as camouflage against the snow so the bears are not seen by their prey. Polar bear skin is actually black, so that it can absorb the invisible warm infrared rays of the sun and the bear’s own body heat, both of which are reflected back by the guard hairs.

Most warm-blooded animals raise their body temperatures through exercise. Polar bears hunt seals, which they don’t often chase. They prefer to sit at the edge of an ice floe and wait for dinner to arrive. At best, they’ll lumber after a seal at four and a half miles (7.25 km) an hour, raising their body heat to 100°F (38°C). When that happens, they go for a swim to cool off.

Cold won’t kill off the polar bears, but global warming can. As polar ice disappears, so does the hunting ground for seals. Not so cool!

​The polar bear is the largest land carnivore. Its long non-retractable claws help it get a grip on the icy surface it prowls for prey. Wikimedia Commons

Close up, the polar bear guard hairs are transparent. This allows the infra-red light (heat) from the sun to pass through them to be absorbed by the black skin under the hairs. The hairs also act like mirrors , reflecting back to the skin any infra-red radiation escaping from the bears body so it can be reabsorbed. Thus, the insulation is just about perfect with no infra-red radiation escaping. The hairs are also coated with oil so they drain quickly after a swim.

The polar bears’ white appearance serves as ideal camouflage in a snow-covered environment. Art by Barbara Lavelle from This Place is Cold by Vicki Cobb.

Vicki Cobb'sThis Place Is Coldshows how the latitude of Alaska affects the lives of the plants, animals and people who live there. It is gloriously illustrated by Barbara Lavallee, a long-time Alaskan resident and artist.

Vicki is a member of Authors on Call—she can visit your classroom with interactive videoconferencing: Read more about her here.

Are your two nostrils exactly the same size? Don’t struggle to find out by looking in a small mirror. Put your nose right above the mirror and breathe down on it. You will see two circles of moisture as the warm moist air from your nose condenses into water when it hits the cool mirror surface. One circle will be a LOT larger than the other.

You might conclude that yes, one nostril is bigger than the other; that you will have to live with being lopsided. But wait! I mean wait an hour or so and do it again. Surprise! This time the small nostril is now the BIG one! The larger nostril is dominant and takes in more of the air. You can do scientific study of your nose and see just how long each nostril dominates. Perhaps if you check often enough, you’ll discover a time when the two circles will be about the same size. This will be the moment of the changing of the nostrils. Of course, you have to do this study when you don’t have a stuffy nose.

What’s behind this? It seems that your nostrils are on an automatic timer from your brain so that they take turns being dominant. It’s very interesting. But I’m not sure if it is important.

Not many people know about this. But your dentist might. A dentist is always looking at peoples’ nostrils. See if your dentist knows about this. He or she might even know why this happens. This just might be a medical mystery worth investigating. And you might be just the one to do it.

Vicki Cobb ‘s “Discover Your Senses” series of books are available through the iTunes store. She begins by asking: “Know how to stop smelling? Hold your nose.” Also, check your library for copies. I mean wait an hour or so and do it again. ​Vicki is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Clickhereto find out more.

You thought Halloween was full of ghosts, goblins and ghouls? Well, wait until the post-Halloween season. This is when your Jack O' Lantern begins its ghoulish decline. It starts as a pumpkin and it ends as a heap of goo. This is scary!

Now is when your Halloween pumpkin begins to rot. Don't get me wrong. Rot is not gross. It is a beautiful thing—beautiful in its own deliciously disgusting way.

You start with a proud Jack, a plump, shiny-skinned pumpkin. Halloween is over so you leave it on your porch, or inside by the window, or maybe you toss it into the garden or onto the compost heap.

It attracts some visitors. A squirrel. A pair of mice. A scurry of sow bugs. They chew the skin of the pumpkin, leaving moist, rough surfaces, just perfect for the next wave of invaders: the molds and fungi and bacteria that start to grow. There are dozens, even hundreds, of types of organisms waiting to sink their "teeth" into pumpkin flesh as soon as the conditions are right. One kind of invader changes the conditions of the flesh to make it perfect for the next one. Meanwhile, the poor pumpkin is looking less and less like a pumpkin. Its skin turns to shades of black, gray and white, with only a few patches of dull orange. Its shape collapses into a heap, then a pile of mush, and then . . . well, no shape at all.

Do you think rot rots? Imagine what your life would be like if things didn't rot. You'd be tripping over all the old pumpkins, not to mention mice, eagles, tomato plants, oak trees and everything else that ever walked, flew, swam or grew upon the earth. Their dead bodies simply wouldn't go away! Worse, their nutrients would be locked forever inside. The energy in the molecules they are made of would be unavailable to any other living things. Rot, properly known as "decomposition," releases all those good vitamins, sugars, proteins, carbohydrates and energy so that they can be used by next year's pumpkin, which will grow from the seeds of last year's pumpkin. Mice and eagles, tomatoes and the trees in a nearby forest can grow and reproduce because nutrients and energy pass through complex food webs from plants to the animals that eat those plants, to other animals that eat those animals.

It's all possible because of rot. So you see, rot doesn't rot. Rot rocks!

Going....

...going...

...gone!

David is the author of > 50 books on math and science, including his newest, rottenest title, Rotten Pumpkin. For more information, click here.

David is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click hereto find out more.

*NEWSFLASH*September, 2018: iNK begins its fifth year of publication of the Nonfiction Minute-- an amazing free resource with more than 4 million page views.

*NEWSFLASH *The NCSS-CBC Notable Social Studies Committee is pleased to inform youthat 30 People Who Changed the World has been selected for Notable Social Studies Trade Books for Young People 2018, a cooperative project of the National Council for the Social Studies (NCSS) & the Children’s Book Council